Friday, September 12, 2014

Bridges Across River Thames

When we set foot on London Bridge on 12 August 2014, we couldn't help but hummed the nursery rhyme "London Bridge is Falling Down".

The bridge we see today is very much different from the earlier versions of London Bridge during the 1210-1600 era. At one time, there were some 200 buildings on the bridge, some stood 7-storey high and some overhung the river by 7 feet and some overhung the road to form tunnel through which traffic passed. The bridge was a human settlement rather than a structure that spanned across a river for traffic and movement of people and goods!

Old medieval London Bridge

We did learn a fair amount of the history of London Bridge in "The London Bridge Experience" - a tour intended to educate but with a bit of horror.


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The Tower Bridge, an iconic symbol of London was built over eight years starting from 1886. Considered an engineering marvel because it was built to solve two problems - allowed vehicular and pedestrian traffic across the river and at the same time permitted ships to cross through the bridge unobstructed.

The bridge consists of two towers tied together at the upper level by means of two horizontal walkways, designed to withstand the horizontal forces exerted by the suspended sections of the bridge on the landward sides of the towers. The vertical components of the forces in the suspended sections and the vertical reactions of the two walkways are supported by two massive towers. The bascule pivots operating machinery are housed in the base of each tower.

1984 vs 2014

The Walkway now serves as exhibition hall.


The massive engines installed to power the hydraulic system which raises the two bascules when passage of tall ships across the bridge is required.

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Today, there are something likes 33 bridges spanning across River Thames in London. With the advancement of bridge engineering, they come in all shapes and sizes. We did catch a glimpse of some of them when we took the river cruise along Thames.

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